Method for forming a via in a substrate and substrate with a via

ABSTRACT

The present invention relates to a method for forming a via in a substrate and a substrate with a via. The method for forming a via in a substrate includes the following steps: (a) providing a substrate having a first surface and a second surface; (b) forming a groove that has a side wall and a bottom wall on the first surface of the substrate; (c) forming a first conductive metal on the side wall and the bottom wall of the groove so as to form a central groove; (d) forming a center insulating material in the central groove; (e) forming an annular groove that surrounds the first conductive metal on the first surface of the substrate; (f) forming a first insulating material in the annular groove; and (g) removing part of the second surface of the substrate to expose the first conductive metal, the center insulating material and the first insulating material. As a result, thicker insulating material can be formed in the via, and the thickness of the insulating material in the via is even.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a method for forming a via in asubstrate and a substrate with a via, and more particularly to a methodfor forming an insulating layer on a side wall of a via in a substrateby utilizing a polymer and a substrate with the via.

2. Description of the Related Art

FIGS. 1 to 3 show schematic views of a conventional method for forming avia in a substrate. First, referring to FIG. 1, a substrate 1 isprovided. The substrate 1 has a first surface 11 and a second surface12.

Afterward, a plurality of grooves 13 are formed on the first surface 11of the substrate 1. An insulating layer 14 is then formed on the sidewall of the grooves 13 by chemical vapor deposition, and a plurality ofaccommodating spaces 15 are formed. The material of the insulating layer14 is usually silicon dioxide.

Afterward, referring to FIG. 2, the accommodating spaces 15 are filledwith a conductive metal 16. The material of the conductive metal 16 isusually copper. Finally, the first surface 11 and the second surface 12of the substrate 1 are ground or etched so as to expose the conductivemetal 16, as shown in FIG. 3.

In the conventional method, the insulating layer 14 is formed bychemical vapor deposition, so that the thickness of the insulating layer14 on the side wall of the grooves 13 is limited, and is usually under0.5 μm.

Moreover, the thickness of the insulating layer 14 on the side wall ofthe grooves 13 is not even, that is, the thickness of the insulatinglayer 14 on the upper side wall of the grooves 13 is not exactly equalto that on the lower side wall of the grooves 13. Thus, the electricalcapacity is not uniform.

Therefore, it is necessary to provide a method for forming a via in asubstrate to solve the above problems.

SUMMARY OF THE INVENTION

The present invention is directed to a method for forming a via in asubstrate. The method comprises the following steps: (a) providing asubstrate having a first surface and a second surface; (b) forming agroove that has a side wall and a bottom wall on the first surface ofthe substrate; (c) forming a first conductive metal on the side wall andthe bottom wall of the groove so as to form a central groove; (d)forming a center insulating material in the central groove; (e) formingan annular groove that surrounds the first conductive metal on the firstsurface of the substrate; (f) forming a first insulating material in theannular groove; and (g) removing part of the second surface of thesubstrate to expose the first conductive metal, the center insulatingmaterial and the first insulating material.

The present invention is further directed to a method for forming a viain a substrate. The method comprises the following steps: (a) providinga substrate having a first surface and a second surface; (b) forming anannular groove and a pillar on the first surface of the substrate sothat the annular groove surrounds the pillar; (c) forming a firstinsulating material in the annular groove; (d) removing the pillar ofthe substrate so as to form a groove that has a side wall and a bottomwall on the substrate; (e) forming a first conductive metal on the sidewall and the bottom wall of the groove so as to form a central groove;(f) forming a center insulating material in the central groove; and (g)removing part of the second surface of the substrate to expose the firstconductive metal, the first insulating material and the centerinsulating material.

The present invention is further directed to a substrate with a via. Thesubstrate comprises a substrate, a first insulating material, a centerinsulating material and a first conductive metal. The substrate has afirst surface, a second surface and a via. The via penetrates thesubstrate, and has an inner side wall. The first insulating material isa hollow pillar disposed on the inner side wall of the via. The centerinsulating material is a solid pillar, disposed at the center of thevia, and spaced from the first insulating material. The first conductivemetal is disposed between the first insulating material and the centerinsulating material, and surrounds the center insulating material so asto form a hollow pillar.

The present invention is further directed to a substrate with a via. Thesubstrate comprises a substrate, a first insulating material and aplurality of grooves. The substrate has a first surface, a secondsurface and a via. The via penetrates the substrate, and has an innerside wall. The first insulating material is disposed in the via andadhered to the inner side wall of the via. The grooves are disposed inthe first insulating material; each of the grooves penetrates the firstinsulating material, and comprises a third insulating material and athird conductive metal. The third insulating material is a solid pillardisposed at the center of the groove, and the third conductive metalsurrounds the third insulating material.

In the present invention, thicker insulating material can be formed inthe via. Also, the thickness of the insulating material in the via iseven. Moreover, the polymer is used as an insulating material in thepresent invention, so polymers with different materials can be chosenfor specific processes.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1 to 3 are schematic views of a conventional method for forming avia in a substrate;

FIGS. 4 to 21 are schematic views of a method for forming a via in asubstrate according to a first embodiment of the present invention;

FIGS. 22 to 39 are schematic views of a method for forming a via in asubstrate according to a second embodiment of the present invention;

FIG. 40 is a schematic view of a substrate with a via according to athird embodiment of the present invention;

FIGS. 41 and 42 are schematic views of a substrate with a via accordingto a fourth embodiment of the present invention; and

FIGS. 43 and 44 are schematic views of a substrate with a via accordingto a fifth embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

FIGS. 4 to 21 show schematic views of a method for forming a via in asubstrate according to a first embodiment of the present invention.Referring to FIG. 4, a top view of the substrate, and FIG. 5, across-sectional view along line 5-5 in FIG. 4, first, a substrate 21 isprovided. The substrate 21 has a first surface 211 and a second surface212. The substrate 21 is, for example, a wafer or a silicon substrate.Afterward, a groove 231 (FIG. 6) is formed on the first surface 211 ofthe substrate 21. The groove 231 has a side wall 232 and a bottom wall233. In the embodiment, a first photo resist layer 241 is formed on thefirst surface 211 of the substrate 21, and a first opening 242 is formedon the first photo resist layer 241.

Referring to FIG. 6, the groove 231 is formed on the substrate 21 byetching according to the first opening 242. The groove 231 is disposedon the first surface 211 of the substrate 21, and has the side wall 232and the bottom wall 233. The first photo resist layer 241 is thenremoved.

Referring to FIG. 7, a first conductive metal 222 is formed on the sidewall 232 and the bottom wall 233 of the groove 231 and the first surface211 of the substrate 21 by electroplating, so as to form a centralgroove 234. In the embodiment, the material of the first conductivemetal 222 is copper.

Afterward, referring to FIGS. 8 to 12, a center insulating material 223is formed in the central groove 234. In the embodiment, the centerinsulating material 223 is a polymer 263. In the present invention, themethod for forming the center insulating material 223 in the centralgroove 234 includes but is not limited to the following three methods.

The first method is that the polymer 263 is dispersed on the firstsurface 211 of the substrate 21, and the position of the polymer 263corresponds to the central groove 234, as shown in FIG. 8.Alternatively, the polymer 263 can be partially dispersed at a positioncorresponding to the central groove 234. Afterward, the polymer 263 isimpelled into the central groove 234 by vacuuming so as to form thecenter insulating material 223, as shown in FIG. 9.

The second method is that a plurality of first vents 237 are formed toconnect the central groove 234 to the second surface 212 of thesubstrate 21, as shown in FIG. 10, a top view of the substrate 21, andFIG. 11, a cross-sectional view along line 11-11 in FIG. 10. Afterward,the polymer 263 is dispersed on the first surface 211 of the substrate21, and the position of the polymer 263 corresponds to the centralgroove 234. Alternatively, the polymer 263 can be partially dispersed ata position corresponding to the central groove 234. The central groove234 and the first vents 237 are then filled with the polymer 263 so asto form the center insulating material 223.

The third method is that the polymer 263 is atomized and deposited inthe central groove 234 by spray coating so as to form the centerinsulating material 223, as shown in FIG. 12.

Afterward, referring to FIG. 13, the first conductive metal 222 and thecenter insulating material 223 disposed on the first surface 211 of thesubstrate 21 are removed by etching or grinding.

Referring to FIGS. 14 and 15, an annular groove 235 is formed on thefirst surface 211 of the substrate 21. The annular groove 235 surroundsthe first conductive metal 222. Referring to FIG. 14, in the embodiment,a second photo resist layer 243 is formed on the first surface 211 ofthe substrate 21, and a second opening 244 is formed on the second photoresist layer 243. The position of the second opening 244 corresponds tothe groove 231, and the diameter of the second opening 244 is largerthan that of the groove 231. Afterward, referring to FIG. 15, theannular groove 235 is formed on the substrate 21 by etching according tothe second opening 244. The annular groove 235 surrounds the firstconductive metal 222, and does not penetrate the substrate 21. Thesecond photo resist layer 243 is then removed.

Referring to FIGS. 16 to 20, a first insulating material 221 is formedin the annular groove 235. In the embodiment, the first insulatingmaterial 221 is polymer 261. In the present invention, the method forforming the first insulating material 221 in the annular groove 235includes but is not limited to the following three methods.

The first method is that the polymer 261 is dispersed on the firstsurface 211 of the substrate 21, and the position of the polymer 261corresponds to the annular groove 235, as shown in FIG. 16.Alternatively, the polymer 261 can be partially dispersed at a positioncorresponding to the annular groove 235. Afterward, the polymer 261 isimpelled into the annular groove 235 by vacuuming so as to form thefirst insulating material 221, as shown in FIG. 17.

The second method is that a plurality of second vents 238 are formed toconnect the annular groove 235 to the second surface 212 of thesubstrate 21, as shown in FIG. 18, a top view of the substrate 21, andFIG. 19, a cross-sectional view along line 19-19 in FIG. 18. Afterward,the polymer 261 is dispersed on the first surface 211 of the substrate21, and the position of the polymer 261 corresponds to the annulargroove 235.

Alternatively, the polymer 261 can be partially dispersed at a positioncorresponding to the annular groove 235. The annular groove 235 and thesecond vents 238 are then filled with the polymer 261 so as to form thefirst insulating material 221.

The third method is that the polymer 261 is atomized and deposited inthe annular groove 235 by spray coating so as to form the firstinsulating material 221, as shown in FIG. 20.

Afterward, referring to FIG. 21, part of the first surface 211 and partof the second surface 212 of the substrate 21 are removed by etching orgrinding so as to expose the first conductive metal 222, the centerinsulating material 223 and the first insulating material 221. Asubstrate 2 with a via according to the first embodiment of the presentinvention is formed. In the embodiment, the via is formed by the centerinsulating material 223, the first conductive metal 222 and the firstinsulating material 221. In the present invention, thicker insulatingmaterial (the center insulating material 223 and the first insulatingmaterial 221) can be formed in the central groove 234 and the annulargroove 235 of the via. Also, the thickness of the insulating material inthe central groove 234 and the annular groove 235 of the via is even.Moreover, the polymer is used as an insulating material in the presentinvention, so polymers with different materials can be chosen forspecific processes.

FIGS. 22 to 39 show schematic views of a method for forming a via in asubstrate according to a second embodiment of the present invention.Referring to FIG. 22, a top view of the substrate, and FIG. 23, across-sectional view along line 23-23 in FIG. 22, first, a substrate 31is provided. The substrate 31 has a first surface 311 and a secondsurface 312. The substrate 31 is, for example, a wafer or a siliconsubstrate. Afterward, referring to FIG. 24, an annular groove 335 and apillar 336 are formed on the first surface 311 of the substrate 31, andthe annular groove 335 surrounds the pillar 336.

In the embodiment, a first photo resist layer 341 is formed on the firstsurface 311 of the substrate 31, a first pattern 342 is formed on thefirst photo resist layer 341, and the first pattern 342 is an annularopening, as shown in FIGS. 22 and 23. Referring to FIG. 24, the annulargroove 335 and the pillar 336 are formed on the substrate 31 by etchingaccording to the first pattern 342. The annular groove 335 surrounds thepillar 336, and the annular groove 335 does not penetrate the substrate31. The first photo resist layer 341 is then removed.

Referring to FIGS. 25 to 29, a first insulating material 321 is formedin the annular groove 335. In the embodiment, the first insulatingmaterial 321 is polymer 361. In the present invention, the method forforming the first insulating material 321 in the annular groove 335includes but is not limited to the following three methods.

The first method is that the polymer 361 is dispersed on the firstsurface 311 of the substrate 31, and the position of the polymer 361corresponds to the annular groove 335, as shown in FIG. 25.Alternatively, the polymer 361 can be partially dispersed at a positioncorresponding to the annular groove 335. Afterward, the polymer 361 isimpelled into the annular groove 335 by vacuuming so as to form thefirst insulating material 321, as shown in FIG. 26. Finally, part of thepolymer 361 which is outside the annular groove 335 is removed.

The second method is that a plurality of second vents 338 are formed toconnect the annular groove 335 to the second surface 312 of thesubstrate 31, as shown in FIG. 27, a top view of the substrate 31, andFIG. 28, a cross-sectional view along line 28-28 in FIG. 27. Afterward,the polymer 361 is dispersed on the first surface 311 of the substrate31, and the position of the polymer 361 corresponds to the annulargroove 335. Alternatively, the polymer 361 can be partially dispersed ata position corresponding to the annular groove 335. The annular groove335 and the second vents 338 are then filled with the polymer 361 so asto form the first insulating material 321. Finally, part of the polymer361 which is outside the annular groove 335 and the second vents 338 isremoved.

The third method is that the polymer 361 is atomized and deposited inthe annular groove 335 by spray coating so as to form the firstinsulating material 321, as shown in FIG. 29. Referring to FIG. 30, partof the polymer 361 which is outside the annular groove 335 is removed.

Referring to FIGS. 31 and 32, the pillar 336 of the substrate 31 isremoved so as to form a groove 331 on the substrate 31. The groove 331has a side wall 332 and a bottom wall 333. In the embodiment, referringto FIG. 31, a second photo resist layer 343 is formed on the firstsurface 311 of the substrate 31. A second opening 344 is formed on thesecond photo resist layer 343, and the position of the second opening344 corresponds to the pillar 336. Afterward, the pillar 336 is removedby dry etching or wet etching according to the second opening 344, so asto form the groove 331. The groove 331 has the side wall 332 and thebottom wall 333. The second photo resist layer 343 is then removedimmediately or in a subsequent step.

Referring to FIG. 33, a conductive metal 322 is formed on the side wall332 and the bottom wall 333 of the groove 331 by electroplating, so asto form a central groove 334. In the embodiment, the material of thefirst conductive metal 322 is copper. Part of the first conductive metal322 which is outside the groove 331 is then removed immediately or in asubsequent step.

Afterward, referring to FIGS. 34 to 38, a center insulating material 323is formed in the central groove 334. In the embodiment, the centerinsulating material 323 is a polymer 363. In the present invention, themethod for forming the center insulating material 323 in the centralgroove 334 includes but is not limited to the following three methods.

The first method is that the polymer 363 is dispersed on the firstsurface 311 of the substrate 31, and the position of the polymer 363corresponds to the central groove 334, as shown in FIG. 34.Alternatively, the polymer 363 can be partially dispersed at a positioncorresponding to the central groove 334. Afterward, the polymer 363 isimpelled into the central groove 334 by vacuuming so as to form thecenter insulating material 323, as shown in FIG. 35.

The second method is that a plurality of first vents 337 are formed toconnect the central groove 334 to the second surface 312 of thesubstrate 31, as shown in FIG. 36, a top view of the substrate 31, andFIG. 37, a cross-sectional view along line 37-37 in FIG. 36. Afterward,the polymer 363 is dispersed on the first surface 311 of the substrate31, and the position of the polymer 363 corresponds to the centralgroove 334. Alternatively, the polymer 363 can be partially dispersed ata position corresponding to the central groove 334. The central groove334 and the first vents 337 are then filled with the polymer 363 so asto form the center insulating material 323.

The third method is that the polymer 363 is atomized and deposited inthe central groove 334 by spray coating so as to form the centerinsulating material 323, as shown in FIG. 38.

Afterward, referring to FIG. 39, part of the first surface 311 and partof the second surface 312 of the substrate 31 are removed by etching orgrinding so as to expose the first conductive metal 322, the centerinsulating material 323 and the first insulating material 321. Asubstrate 3 with a via according to the second embodiment of the presentinvention is formed.

FIG. 40 shows a schematic view of a substrate with a via according to athird embodiment of the present invention. The substrate 4 with a viacomprises a substrate 41, a first insulating material 421, a centerinsulating material 423 and a first conductive metal 422.

The substrate 41 has a first surface 411, a second surface 412 and a via413. The via 413 penetrates the substrate 41, and has an inner side wall414. The first insulating material 421 is a hollow pillar disposed onthe inner side wall 414 of the via 413. The center insulating material423 is a solid pillar, disposed at the center of the via 413, and spacedfrom the first insulating material 421. The first conductive metal 422is disposed between the first insulating material 421 and the centerinsulating material 423, and surrounds the center insulating material423 so as to form a hollow pillar. In the embodiment, the firstinsulating material 421 contacts the first conductive metal 422, and thecenter insulating material 423 contacts the first conductive metal 422.That is, a three-layered structure with insulating material andconductive material in alternate layers is formed in the via 413, andthe structure includes the center insulating material 423, the firstconductive metal 422 and the first insulating material 421 from thecenter to the edge. The center insulating material 423 and the firstinsulating material 421 may be the same or different.

The substrate 4 with a via further comprises a passivation layer 451 anda conducting layer 453. The passivation layer 451 is disposed on thefirst surface 411 or the second surface 412 of the substrate 41. In theembodiment, the passivation layer 451 is disposed on the first surface411 of the substrate 41. The passivation layer 451 has an opening 452,so that the passivation layer 451 covers part of the first insulatingmaterial 421 and exposes part of the first insulating material 421. Theconducting layer 453 is disposed on the passivation layer 451, andcovers part of the first insulating material 421, the first conductivemetal 422 and the center insulating material 423.

FIGS. 41 and 42 show schematic views of a substrate with a via accordingto a fourth embodiment of the present invention. FIG. 41 is a top viewof the substrate, and FIG. 42 is a cross-sectional view along line 42-42in FIG. 41. The substrate 5 with a via comprises a substrate 51, a firstinsulating material 521, a center insulating material 523, a firstconductive metal 522, a second insulating material 525 and a secondconductive metal 524.

The substrate 51 has a first surface 511, a second surface 512 and a via513. The via 513 penetrates the substrate 51, and has an inner side wall514. The first insulating material 521 is a hollow pillar disposed onthe inner side wall 514 of the via 513. The center insulating material523 is a solid pillar, disposed at the center of the via 513, and spacedfrom the first insulating material 521. The first conductive metal 522is disposed between the center insulating material 523 and the secondinsulating material 525, and surrounds the center insulating material523 so as to form a hollow pillar. The second insulating material 525 isdisposed between the first conductive metal 522 and the secondconductive metal 524, and surrounds the first conductive metal 522 so asto form a hollow pillar. The second conductive metal 524 is disposedbetween the second insulating material 515 and the first insulatingmaterial 521, and surrounds the second insulating material 525 so as toform a hollow pillar. In the embodiment, the second insulating material525 contacts the first conductive metal 522, the second conductive metal524 contacts the second insulating material 525, and the secondconductive metal 524 contacts the first insulating material 521. Thatis, a five-layered structure with insulating material and conductivematerial in alternate layers is formed in the via 513, and the structureincludes the center insulating material 523, the first conductive metal522, the second insulating material 525, the second conductive metal 524and the first insulating material 521 from the center to the edge. Thecenter insulating material 523, the first insulating material 521 andthe second insulating material 525 may be the same or different. Thematerial of the first conductive metal 522 and the second conductivemetal 524 may be the same or different.

Moreover, it is understood that, in the substrate 5 with a via, morelayers of insulating material and conductive metal can be placed betweenthe center insulating material 523 and the first insulating material521, so as to form a multi-layered structure with insulating materialand conductive material in alternate layers.

FIGS. 43 and 44 show schematic views of a substrate with a via accordingto a fifth embodiment of the present invention. FIG. 43 is a top view ofthe substrate, and FIG. 44 is a cross-sectional view along line 44-44 inFIG. 43. The substrate 6 with a via comprises a substrate 61, a firstinsulating material 621 and a plurality of grooves 629.

The substrate 61 has a first surface 611, a second surface 612 and a via613. The via 613 penetrates the substrate 61, and has an inner side wall614. The first insulating material 621 is disposed in the via 613, andattached to the inner side wall 614 of the via 613. The grooves 629 aredisposed in the first insulating material 621. Each of the grooves 629penetrates the first insulating material 621, and comprises a thirdinsulating material 627 and a third conductive metal 626. The thirdinsulating material 627 is a solid pillar, and disposed at the center ofthe grooves 629. The third conductive metal 626 surrounds and contactsthe third insulating material 627, and contacts the first insulatingmaterial 621. The first insulating material 621 and the third insulatingmaterial 627 may be the same or different.

Moreover, it is understood that, in the substrate 6 with a via, morelayers of insulating material and conductive metal may be placed betweenthe third insulating material 627 and the third conductive metal 626 ofeach of the grooves 629, or between the third conductive metal 626 andthe first insulating material 621 of each of the grooves 629, so as toform a multi-layered structure with insulating material and conductivematerial in alternate layers.

The substrate 6 with a via further comprises a passivation layer (notshown) and a conducting layer (not shown). The passivation layer isdisposed on the first surface 611 or the second surface 612 of thesubstrate 61, and has a plurality of openings. The position of each ofthe openings of the passivation layer corresponds to each of the grooves629, and the diameter of each of the openings of the passivation layeris larger than that of each of the grooves 629, so that the passivationlayer covers part of the first insulating material 621 and exposes partof the first insulating material 621. The conducting layer is disposedon the passivation layer, and covers part of the first insulatingmaterial 621, the third conductive metal 626 and the third insulatingmaterial 627.

While several embodiments of the present invention have been illustratedand described, various modifications and improvements can be made bythose skilled in the art. The embodiments of the present invention aretherefore described in an illustrative but not restrictive sense. It isintended that the present invention should not be limited to theparticular forms as illustrated, and that all modifications whichmaintain the spirit and scope of the present invention are within thescope defined in the appended claims.

1. A method for forming a via in a substrate, comprising: (a) providinga substrate having a first surface and a second surface; (b) forming agroove that has a side wall and a bottom wall on the first surface ofthe substrate; (c) forming a first conductive metal on the side wall andthe bottom wall of the groove so as to form a central groove; (d)forming a center insulating material in the central groove; (e) formingan annular groove that surrounds the first conductive metal on the firstsurface of the substrate; (f) forming a first insulating material in theannular groove; and (g) removing part of the second surface of thesubstrate to expose the first conductive metal, the center insulatingmaterial and the first insulating material.
 2. The method as claimed inclaim 1, wherein Step (b) comprises: (b1) forming a first photo resistlayer on the first surface of the substrate; (b2) forming a firstopening on the first photo resist layer; and (b3) forming the groove onthe substrate according to the first opening.
 3. The method as claimedin claim 1, wherein Step (d) comprises: (d1) dispersing a polymer at aposition corresponding to the central groove; and (d2) impelling thepolymer into the central groove by vacuuming so as to form the centerinsulating material.
 4. The method as claimed in claim 1, wherein Step(d) comprises: (d1) forming a plurality of first vents so as to connectthe central groove to the second surface of the substrate; (d2)dispersing a polymer at a position corresponding to the central groove;and (d3) filling the central groove and the first vents with the polymerso as to form the center insulating material.
 5. The method as claimedin claim 1, wherein Step (e) comprises: (e1) forming a second photoresist layer on the first surface of the substrate; (e2) forming asecond opening on the second photo resist layer so that the position ofthe second opening corresponds to the groove, and the diameter of thesecond opening is larger than that of the groove; and (e3) forming theannular groove on the substrate according to the second opening.
 6. Themethod as claimed in claim 1, wherein in Step (e), the annular groovedoes not penetrate the substrate.
 7. The method as claimed in claim 1,wherein Step (f) comprises: (f1) dispersing a polymer at a positioncorresponding to the annular groove; and (f2) impelling the polymer intothe annular groove by vacuuming so as to form the first insulatingmaterial.
 8. The method as claimed in claim 1, wherein Step (f)comprises: (f1) forming a plurality of second vents so as to connect theannular groove to the second surface of the substrate; (f2) dispersing apolymer at a position corresponding to the annular groove; and (d3)filling the annular groove and the second vents with the polymer so asto form the first insulating material.
 9. A method for forming a via ina substrate, comprising: (a) providing a substrate having a firstsurface and a second surface; (b) forming an annular groove and a pillaron the first surface of the substrate so that the annular groovesurrounds the pillar; (c) forming a first insulating material in theannular groove; (d) removing the pillar of the substrate so as to form agroove that has a side wall and a bottom wall on the substrate; (e)forming a first conductive metal on the side wall and the bottom wall ofthe groove so as to form a central groove; (f) forming a centerinsulating material in the central groove; and (g) removing part of thesecond surface of the substrate to expose the first conductive metal,the first insulating material and the center insulating material. 10.The method as claimed in claim 9, wherein Step (b) comprises: (b1)forming a first photo resist layer on the first surface of thesubstrate; (b2) forming a first pattern on the first photo resist layer;and (b3) forming the annular groove and the pillar on the substrateaccording to the first pattern.
 11. The method as claimed in claim 9,wherein Step (c) comprises: (c1) dispersing a polymer at a positioncorresponding to the annular groove; (c2) impelling the polymer into theannular groove by vacuuming so as to form the first insulating material;and (c3) removing the polymer which is outside the annular groove. 12.The method as claimed in claim 9, wherein Step (c) comprises: (c1)forming a plurality of first vents so as to connect the annular grooveto the second surface of the substrate; (c2) dispersing a polymer at aposition corresponding to the annular groove; (c3) filling the annulargroove and the first vents with the polymer so as to form the firstinsulating material; and (c4) removing the polymer which is outside theannular groove and the first vents.
 13. The method as claimed in claim9, wherein Step (c) comprises: (c1) atomizing and depositing a polymerin the annular groove by spray coating so as to form the firstinsulating material; and (c2) removing the polymer which is outside theannular groove.
 14. The method as claimed in claim 9, wherein Step (d)comprises: (d1) forming a second photo resist layer on the first surfaceof the substrate; (d2) forming a second opening on the second photoresist layer so that the position of the second opening corresponds tothe pillar; and (d3) removing the pillar according to the second openingso as to form the groove.
 15. The method as claimed in claim 9, whereinStep (f) comprises: (f1) dispersing a polymer at a positioncorresponding to the central groove; and (f2) impelling the polymer intothe central groove by vacuuming so as to form the center insulatingmaterial.
 16. The method as claimed in claim 9, wherein Step (f)comprises: (f1) forming a plurality of second vents so as to connect thecentral groove to the second surface of the substrate; (f2) dispersing apolymer at a position corresponding to the central groove; and (f3)filling the central groove and the second vents with the polymer so asto form the center insulating material.
 17. A substrate with a via,comprising: a substrate, having a first surface, a second surface and avia that penetrates the substrate and has an inner side wall; a firstinsulating material, which is a hollow pillar, disposed on the innerside wall of the via; a center insulating material disposed at thecenter of the via, and the center insulating material is a solid pillarspaced from the first insulating material; and a first conductive metal,disposed between the first insulating material and the center insulatingmaterial, and the first conductive metal surrounds the center insulatingmaterial so as to form a hollow pillar.
 18. The substrate as claimed inclaim 17, wherein the first insulating material contacts the firstconductive metal, and the center insulating material contacts the firstconductive metal.
 19. The substrate as claimed in claim 17, furthercomprising a second insulating material and a second conductive metal,disposed between the first conductive metal and the first insulatingmaterial, so that the second insulating material surrounds the firstconductive metal, and the second conductive metal surrounds the secondinsulating material.
 20. The substrate as claimed in claim 19, whereinthe second insulating material contacts the first conductive metal, thesecond conductive metal contacts the second insulating material, and thesecond conductive metal contacts the first insulating material.
 21. Thesubstrate as claimed in claim 17, further comprising a passivation layerand a conducting layer, and the passivation layer is disposed on thefirst surface or the second surface of the substrate, and has anopening, so as to cover part of the first insulating material and exposepart of the first insulating material, and the conducting layer isdisposed on the passivation layer, and covers part of the firstinsulating material, the first conductive metal and the centerinsulating material.
 22. A substrate with a via, comprising: asubstrate, having a first surface, a second surface and a via thatpenetrates the substrate and has an inner side wall; a first insulatingmaterial, disposed in the via, and attached to the inner side wall ofthe via; and a plurality of grooves, disposed in the first insulatingmaterial, so that each of the grooves penetrates the first insulatingmaterial, and comprises a third insulating material and a thirdconductive metal, and the third insulating material is a solid pillardisposed at the center of the grooves, and the third conductive metalsurrounds the third insulating material.
 23. The substrate as claimed inclaim 22, wherein the third conductive metal contacts the thirdinsulating material, and the third conductive metal contacts the firstinsulating material.
 24. The substrate as claimed in claim 22, furthercomprising a passivation layer and a conducting layer, and thepassivation layer is disposed on the first surface or the second surfaceof the substrate, and has a plurality of openings; the position of eachof the openings of the passivation layer corresponds to each of thegrooves, the diameter of each of the openings of the passivation layeris larger than that of each of the grooves, so that the passivationlayer covers part of the first insulating material and exposes part ofthe first insulating material; the conducting layer is disposed on thepassivation layer, and covers part of the first insulating material, thethird conductive metal and the third insulating material.